Fuel Cells for Auxiliary Power in Trucks: Requirements, Benefits and Marketability

Public agencies and the trucking industry have recognized the idling of heavy-duty trucks as a significant contributor to fuel consumption and air pollution. Several potential technical solutions are in development, including the utilization of auxiliary power units (APUs). Using fuel cell APUs could be a promising alternative to idling with substantial fuel consumption, emissions, cost, and noise benefits, while serving as a niche for relatively early fuel cell technology market introduction. This paper, using a probabilistic Monte Carlo framework, reports on efforts to characterize existing data on idling trucks, develop an ADVISOR-based vehicle APU model that accurately depicts how utilizing fuel cell APUs to replace heavy-duty truck idling could be implemented, quantify energy consumption reductions, and analyze the economic benefits of the APU. The analysis shows that if fuel cell research targets for APUs are met over the next decade, a market in the tens of thousands of units may be possible in the line-haul trucking industry, and substantial diesel consumption reductions would result

Marginalization of end-use technologies in energy innovation for climate protection

Mitigating climate change requires directed innovation efforts to develop and deploy energy technologies. Innovation activities are directed towards the outcome of climate protection by public institutions, policies and resources that in turn shape market behaviour. We analyse diverse indicators of activity throughout the innovation system to assess these efforts. We find efficient end-use technologies contribute large potential emission reductions and provide higher social returns on investment than energy-supply technologies. Yet public institutions, policies and financial resources pervasively privilege energy-supply technologies. Directed innovation efforts are strikingly misaligned with the needs of an emissions-constrained world. Significantly greater effort is needed to develop the full potential of efficient end-use technologies

Canada’s Voluntary Agreement on Vehicle Greenhouse Gas Emissions: When the Details Matter

The 2005 voluntary agreement between the automobile industry and Canadian government to reduce greenhouse gas emissions from passenger vehicles is evaluated. We analyze the likely effect of the agreement on emissions, and on use of biofuels and advanced vehicle technologies. We conclude that the impact on emissions could be far less than suggested, possibly even zero, even if automobile companies fully comply. The pros and cons of the Canadian agreement are assessed and compared with other voluntary and mandatory greenhouse gas reduction programs. Some lessons learned include the importance of specific performance metrics to evaluate progress, use of precise baseline measurements and methods, and an appreciation of the asymmetry in information between most governments and the affected industries

Association of lipid-related genetic variants with the incidence of atrial fibrillation: The AFGen consortium

Background: Several studies have shown associations between blood lipid levels and the risk of atrial fibrillation (AF). To test the potential effect of blood lipids with AF risk, we assessed whether previously developed lipid gene scores, used as instrumental variables, are associated with the incidence of AF in 7 large cohorts. Methods: We analyzed 64,901 individuals of European ancestry without previous AF at baseline and with lipid gene scores. Lipid-specific gene scores, based on loci significantly associated with lipid levels, were calculated. Additionally, non-pleiotropic gene scores for high-density lipoprotein cholesterol (HDLc) and low-density lipoprotein cholesterol (LDLc) were calculated using SNPs that were only associated with the specific lipid fraction. Cox models were used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) of AF per 1-standard deviation (SD) increase of each lipid gene score. Results: During a mean follow-up of 12.0 years, 5434 (8.4%) incident AF cases were identified. After meta-analysis, the HDLc, LDLc, total cholesterol, and triglyceride gene scores were not associated with incidence of AF. Multivariable-adjusted HR (95% CI) were 1.01 (0.98-1.03); 0.98 (0.96-1.01); 0.98 (0.95-1.02); 0.99 (0.97-1.02), respectively. Similarly, non-pleiotropic HDLc and LDLc gene scores showed no association with incident AF: HR (95% CI) = 1.00 (0.97-1.03); 1.01 (0.99-1.04). Conclusions In this large cohort study of individuals of European ancestry, gene scores for lipid fractions were not associated with incident AF

Synergistic and Non-synergistic Associations for Cigarette Smoking and Non-tobacco Risk Factors for Cardiovascular Disease Incidence in the Atherosclerosis Risk In Communities (ARIC) Study

Cigarette smoking, various metabolic and lipid-related factors and hypertension are well-recognized cardiovascular disease (CVD) risk factors. Since smoking affects many of these factors, use of a single imprecise smoking metric, e.g., ever or never smoked, may allow residual confounding and explain inconsistencies in current assessments of interactions. Using a comprehensive model in pack-years and cigarettes/day for the complex smoking-related relative risk (RR) of CVD to reduce residual confounding, we evaluated interactions with non-tobacco risk factors, including additive (non-synergistic) and multiplicative (synergistic) forms. Data were from the prospective Atherosclerosis Risk in Communities (ARIC) Study from four areas of the U.S. recruited in 1987-89 with follow-up through 2008. Analyses included 14,127 participants, 207,693 person-years and 2,857 CVD events. Analyses revealed distinct interactions with smoking: including statistical consistency with additive (body mass index, waist to hip ratio, diabetes mellitus, glucose, insulin, high density lipoproteins [HDL] and HDL(2)); and multiplicative (hypertension, total cholesterol, low density lipoproteins, apolipoprotein B, total cholesterol to HDL ratio and HDL(3)) associations, as well as indeterminate (apolipoprotein A-I and triglycerides) associations. The forms of the interactions were revealing but require confirmation. Improved understanding of joint associations may help clarify the public health burden of smoking for CVD, links between etiologic factors and biological mechanisms, and the consequences of joint exposures, whereby synergistic associations highlight joint effects and non-synergistic associations suggest distinct contributions. Joint associations for cigarette smoking and non-tobacco risk factors were distinct, revealing synergistic/multiplicative (hypertension, TC, LDL, apoB, TC/HDL, HDL(3)), non-synergistic/additive (BMI, WHR, DM, glucose, insulin, HDL, HDL(2)) and indeterminate (apoA-I and TRIG) associations. If confirmed, these results may help better define the public health burden of smoking on CVD risk and identify links between etiologic factors and biologic mechanisms, where synergistic associations highlight joint impacts and non-synergistic associations suggest distinct contributions from each factor

Forecasts, scenarios, visions, backcasts and roadmaps to the hydrogen economy: a review of the hydrogen futures literature

Scenarios, roadmaps and similar foresight methods are used to cope with uncertainty in areas with long planning horizons, such as energy policy, and research into the future of hydrogen energy has been no exception. Such studies can play an important role in the development of shared visions of the future: creating powerful expectations of the potential of emerging technologies and mobilising resources necessary for their realisation. This paper reviews the hydrogen futures literature, using a six-fold typology to map the state of the art of scenario construction. The paper then explores the expectations embodied in the literature, through the 'answers' it provides to questions about the future of hydrogen. What are the drivers, barriers and challenges facing the development of a hydrogen economy? What are the key technological building blocks required? In what kinds of futures does hydrogen become important? What does a hydrogen economy look like, how and when does it evolve, and what does it achieve? The literature describes a diverse range of possible futures, from decentralised systems based upon the small-scale renewables, through to centralised systems reliant on nuclear energy or carbon-sequestration. There is a broad consensus that the hydrogen economy emerges only slowly, if all under 'Business as Usual' scenarios. Rapid transitions to hydrogen occur only under conditions of strong governmental support combined with, or as a result of, major 'discontinuities' such as shifts in society's environmental values, 'game changing' technological breakthroughs, or rapid increases in the oil price or speed and intensity of climate change

Bioavailability and metabolism of ccompounds from wholegrain wheat and aleurone‐rich wheat bread

Scope: This work aimed at investigating absorption, metabolism and bioavailability of phenolic compounds after consumption of wholegrain bread or bread enriched with an aleurone fraction. Methods and results: Two commercially available breads were consumed by 15 participants on three occasions and matched for either the amount of ferulic acid in the bread or the amount of bread consumed. Urine was collected for 48 h from all the volunteers for phenolic metabolite quantification. Blood samples were collected for 24 h following bread consumption in 5 participants. A total of 12 and 4 phenolic metabolites were quantified in urine and plasma samples, respectively. Metabolites were sulfate and glucuronic acid conjugates of phenolic acids, and high concentrations of ferulic acid-4’-O-sulfate, dihydroferulic acid-4’-O-sulfate and dihydroferulic acid-O-glucuronide were observed. The bioavailability of ferulic acid was significantly higher from the aleurone-enriched bread when all ferulic acid metabolites were accounted for.Conclusions: The study shows that low amounts of aleurone-enriched bread resulted in equivalent plasma levels of ferulic acid as wholegrain bread. This could suggest that, if the absorbed phenolic metabolites after wholegrain product intake exert health benefits, equal levels could be reached through the consumption of lower doses of refined products enriched in aleurone fraction

Physical activity attenuates the influence of FTO variants on obesity risk: A meta-analysis of 218,166 adults and 19,268 children

Background: The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA) may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166) and nine studies of children and adolescents (n = 19,268). Methods and Findings: All studies identified to have data on the FTO rs9939609 variant (or any proxy [r2>0.8]) and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active) in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A-) allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26), but PA attenuated this effect (pinteraction= 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio = 1.22/allele, 95% CI 1.19-1.25) than in the inactive group (odds ratio = 1.30/allele, 95% CI 1.24-1.36). No such interaction was found in children and adolescents. Concl

Dietary intake and peripheral arterial disease incidence in middle-aged adults: the Atherosclerosis Risk in Communities (ARIC) Study

Background: Peripheral arterial disease (PAD) is a costly source of morbidity and mortality among older persons in the United States. Dietary intake plays a role in the development of atherosclerotic cardiovascular disease; however, few studies have examined the relation of food intake or dietary patterns with PAD